Πέμπτη 11 Αυγούστου 2022

Stimulation Rate and Voice Pitch Perception in Cochlear Implants

alexandrossfakianakis shared this article with you from Inoreader
We describe two experiments with 16 Nu cleus® CI users, where we controlled modulation characteristics and carrier rate using Spectral and Temporal Enhanced Processing (STEP), a novel experimental multichannel sound coder. We used a fixed set of threshold and comfortable stimulation levels for each subject, obtained from clinical MAPs. In the first experiment, we determined equivalence for voice pitch ranking and voice gender categorization between the Advanced Combination Encoder (ACE), a widely used clinical strategy in Nucleus® recipients, and STEP for fundamental frequencies (F0) 120–250 Hz. In the second experiment, loudn ess was determined as a function of the input amplitude of speech samples for carrier rates of 1000, 500, and 250 pps per channel. Then, using equally loud soun...
View on Web

Temporal Envelope Coding of the Human Auditory Nerve Inferred from Electrocochleography: Comparison with Envelope Following Responses

alexandrossfakianakis shared this article with you from Inoreader
AbstractNeural coding of the slow amplitude fluctuations of sound (i.e., temporal envelope) is thought to be essential for speech understanding; however, such coding by the human auditory nerve is poorly understood. Here, neural coding of the temporal envelope by the human auditory nerve is inferred from measurements of the compound action potential in response to an amplitude modulated carrier (CAPENV) for modulation frequencies ranging from 20 to 1000  Hz. The envelope following response (EFR) was measured simultaneously with CAPENV from active electrodes placed on the high forehead and tympanic membrane, respectively. Results support the hypothesis that phase locking to higher modulation frequencies (>  80 Hz) will be stronger for CAPENV, compared to EFR, consistent with the uppe...
View on Web

Regenerative endodontic therapy for external lateral inflammatory resorption following traumatic dental injuries. Evidence assessment of best practices

alexandrossfakianakis shared this article with you from Inoreader

Abstract

Introduction

External inflammatory resorption (EIR) following dental trauma is often caused by an injury to the lining of the cementoblasts and to the non-mineralized tissues (i.e., precementum) covering the root surface. Although EIR frequently occurs apically, it can also develop on the lateral root surfaces, which is termed external inflammatory lateral resorption (EILR). ELIR is a severe complication that can lead to significant root loss and tooth extraction.

Aim

The aim of this project was to review the current evidence in the literature on regenerative endodontic therapy (RET) for ELIR following traumatic injuries and assess the best treatment practices.

Methodology

Publications appearing in PubMed electronic database, from January 1, 2001 to January 9, 2022 were studied. Inclusion criteria were: (a) Publications in the English language; (b) Publications on regenerative endodontic therapy and ELIR; (c) Teeth subjected to dental trauma; and (d) Presence of intracanal bleeding and blood clots. Exclusion criteria were: (a) Conference proceedings; (b) Lectures; (c) Abstracts and (d) Letters to the editor; (e) Publications not in the English language. Additionally, a manual search was conducted. The data collected was analysed, and a descriptive statistical analysis was performed.

Results

A total of 355 publications were analysed, of which 9 met all inclusion criteria, which comprised of case reports and case series studies. In 10 (58.8%) teeth, Triple Antibiotic Paste (TAP) was used for an average of 26 days. Double Antibiotic Paste (DAP) was used in 3 (17.6 %) teeth for an average of 14 days. In 3 (17.6 %) cases, calcium hydroxide (Ca(OH)2) was used as intracanal medication for 14 days and negative pressure irrigation was applied once on 1 (6 %) tooth.

Conclusions

RET demonstrated a good treatment modality producing biologic repair and improving prognosis in cases of ELIR in post-traumatic tooth/pulp injuries. Hence, a meticulous follow up should be conducted when RET is performed in order to identify treatment failure and substitute it with long-term Ca(OH)2 root canal dressing. The key limitation in our review is that all publications included were either case reports or case series that usually tend to report successful outcome.

View on Web

Τετάρτη 10 Αυγούστου 2022

The Interplay of Long Non‐Coding RNAs and Hepatitis B Virus

alexandrossfakianakis shared this article with you from Inoreader

ABSTRACT

Hepatitis B Virus (HBV) infections remain a major global health burden with an estimated 296 million people living with a chronic infection and 884,00 HBV-related deaths annually. Notably, patients with a chronic hepatitis B (CHB) infection are at a 30-fold greater risk of developing hepatocellular carcinoma (HCC), the 3rd deadliest cancer worldwide. Several groups have assessed HBV-related aberrant expression of host-cell long non-coding RNAs (lncRNAs) and how altered expression of specific lncRNAs affects HBV replication and progression to associated disease states. Given the challenges in establishing effective HBV models and analyzing transcriptomic data, this review focuses on lncRNA expression data primarily collected from clinical patient samples and primary human hepatocytes (PHHs), with subsequent mechanism of action analysis in cell lines or other model systems. Ultimately, understanding HBV-induced lncRNA-expression dysregulation could lead to new treatments and biomarkers for HBV infection and its associated diseases.

This article is protected by copyright. All rights reserved.

View on Web

A Phase I/II Study of Intrathecal Trastuzumab in HER-2 Positive Cancer with Leptomeningeal Metastases: Safety, Efficacy, and Cerebrospinal Fluid Pharmacokinetics

alexandrossfakianakis shared this article with you from Inoreader
Abstract
Background
Patients with human epidermal growth factor receptor 2-positive (HER2-positive) cancers have a high incidence of central nervous system (CNS) spread, but unfortunately systemic trastuzumab which targets the HER2 receptor has little CNS penetration. The purpose of this study was to determine the maximum tolerated dose of intrathecal trastuzumab and its efficacy in patients with HER2-positive LMD.
Methods
This multicenter study enrolled 34 LMD patients in a combined Phase I/II study in treating patients with intrathecal trastuzumab. Any HER2-positive histology was allowed in the Phase I; the Phase II was limited to HER2-positive breast cancer.
Results
Intrathecal trastuzumab was well tolerated, with one dose limiting toxicity of grade 4 (arachnoiditis) occurring at the 80 mg twice weekly dose. The recommended Phase II dose was 80 mg intrathecally twice weekly. Twenty-six patients at dose level 80mg w ere included in evaluation for efficacy: partial response was seen in 5 (19.2%) patients, stable disease was observed in 13 (50.0%), and 8 (30.8%) of the patients had progressive disease. Median overall survival (OS) for Phase 2 dose treated patients was 8.3 months (95% CI 5.2 to 19.6). The Phase II HER2-positive breast cancer patients median OS was 10.5 months (95% CI 5.2 to 20.9). Pharmacokinetic (PK) studies were limited in the setting of concurrent systemic trastuzumab administration, however, did show stable CSF concentrations with repeated dosing suggest that trastuzumab does not accumulate in the CSF in toxic concentrations.
Conclusion
This study suggests promise for potentially improved outcomes of HER-positive LMD patients when treated with intrathecal trastuzumab while remaining safe and well-tolerated for patients.
View on Web

Τρίτη 9 Αυγούστου 2022

Could red cell distribution width be used for predicting cardiac injury in neonates with COVID‐19?

alexandrossfakianakis shared this article with you from Inoreader

ABSTRACT

Background

Coronavirus disease 2019 (COVID-19) can affect people of all age groups and it can occasionally cause life-threatening clinical illness in immunologically immature population, especially in newborns. High red cell distribution width (RDW) values were used as early prognostic biomarker of some neonatal diseases. We aimed to determine the prognostic value of red cell distribution width in severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infected neonates.

Methods

Newborns with positive SARS-CoV-2 polymerase chain reaction (PCR) test from a nasopharyngeal swab sample, who had refractory fever (>38°C and lasting more than 24 hours during hospitalization) screened for multisystem inflammatory syndrome in newborns (MIS-N), systemic inflammatory indexes calculated and cardiologic evaluation performed to these patients. Due to troponin levels (high: >45 ng/L and low: ≤45 ng/L) patients were grouped.

Results

Of the 68 SARS-CoV-2 PCR-positive newborns, 26 patients had refractory fever. Comparison of laboratory findings between the high and low troponin groups showed that RDW and neutrophil/lymphocyte ratio values were significantly higher in patients with high troponin levels (p = 0.022 and p = 0.030, respectively). The cut-off values with optimal sensitivity and specificity were determined as 1.00 for neutrophil/lymphocyte ratio (p = 0.205) and 16.6 for red cell distribution width (p = 0.014). None of the patients died.

Conclusions

Neonatal coronavirus disease 2019 generally has a benign prognosis, but can progress to severe disease and cases of MIS-N are rare. RDW could be prognostic in diagnosis and management of neonates with SARS-CoV-2 infection with high troponin levels.

This article is protected by copyright. All rights reserved.

View on Web

Δευτέρα 8 Αυγούστου 2022

Initiating Intramuscular Depot Medroxyprogesterone Acetate (DMPA-IM) Increases Frequencies of Th17-like Human Immunodeficiency Virus (HIV) Target Cells in the Genital Tract of Women in South Africa: A Randomized Trial

alexandrossfakianakis shared this article with you from Inoreader

m_ciac284f1.jpeg?Expires=1723090811&Sign

Abstract
BackgroundCervicovaginal CD4+ T cells are preferential targets for human immunodeficiency virus (HIV) infection and have consequently been used as a proxy measure for HIV susceptibility. The ECHO randomized trial offered a unique opportunity to consider the association between contraceptives and Th17-like cells within a trial designed to evaluate HIV risk. In a mucosal substudy of the ECHO trial, we compared the impact of initiating intramuscular depot medroxyprogesterone acetate (DMPA-IM), copper-IUD, and the levonorgestrel (LNG) implant on cervical T cells.
Methods
Cervical cytobrushes from 58 women enrolled in the ECHO trial were collected at baseline and 1 month after contraceptive initiation. We phenotyped cervical T cells using multiparameter flow cytometry, characterized the vaginal microbiome using 16s sequencing, and determined proteomic signatures associated with Th17-like cells using mass spectrometry.
Results
Unlike the LNG implant or copper-IUD, DMPA-IM was as sociated with higher frequencies of cervical Th17-like cells within 1 month of initiation (P = .012), including a highly susceptible, activated population co-expressing CD38, CCR5, and α4β7 (P = .003). After 1 month, women using DMPA-IM also had more Th17-like cells than women using the Cu-IUD (P = .0002) or LNG implant (P = .04). Importantly, in women using DMPA-IM, proteomic signatures signifying enhanced mucosal barrier function were associated with the increased abundance of Th17-like cells. We also found that a non–Lactobacillus-dominant microbiome at baseline was associated with more Th17-like cells post–DMPA-IM (P = .03), although this did not influence barrier function.
Conclusions
Our data suggest that D MPA-IM–driven accumulation of HIV-susceptible Th17-like cells might be counteracted by their role in maintaining mucosal barrier integrity.
View on Web